Coaxial switch



Sept. 6, 1960 R. F. STEWART COAXIAL SWITCH Filed June 50, 1959 UnitedStates COAXIAL swrrcn Robert F. Stewart, Wayland, Mass, assignor toGeneral Communication Company, Boston, Mass., a corporation ofMassachusetts Filed June 30, 19 59, Ser. No. 823,929 I 8 Claims. c1:2005-153 It is another object of the invention to provide a coaxialswitch that is simple to make andtooperate.

It is anotherobject of the invention to provide a coaxial switch whereina minimum of electrical discontinuity is introduced between the selectedlines.

It is another object of the invention to provide a coaxial switch thatis reliable in operation and has a relatively long service life. r

. The novel features of the invention togetherwithfu'r- Patent therobjects and advantages thereof will become apparent from the followingdetailed description and the drawing' to whichit refers;

In the drawing;

Fig. l is a view' of a' vertical sec 'tio'n of the switch according tothe present invention;

Fig. 2 is a sectional view taken on line 22 of Fig. 1;

Fig. 3 is a sectional view taken on line 3-3 of Fig. 1; Fig. 4 is a viewof part of the switch similar to the way it is shown in Fig. 1 but withthe switch actuating element in a different angular position, and

Fig. 5 is a view similar to that of Fig. 4 showing a modification ofthis part of the switch in accordance with the invention.

With reference now to the drawing, it will be observed that the coaxialswitch according to the present invention has a body 11 of conductivematerial wherein two intersecting passageways 12 and 13 are formed. Thefirst passageway 12 extending from left to right in Fig. 1 is circularin section in the regions where it passes out of the body, andessentially rectangular in section inbetween. Also it will be observedthat the left half of this passageway is offset slightly with respect tothe right half.

Disposed at the ends of this passageway are a pair of female coaxialconnectors having outer shells 14, inner conductors 15 and supports 16for their inner conductors. The supports have the shape of a washer andare made of an insulating material such as Teflon. Each outer shell isprovided with external threads and its associated innerconductor isbored for approximately one-half its length.

Also, it has a series of longitudinal slots in it. In this way theconnectors are adapted for use with standard type N fittings, well knownto those skilled in the art.

The opposed ends of the inner conductors 15 are each provided with ahorizontal slot 18, and to keep the inner conductors from turning sothat these slots remain horizontal, positioning pins 19 are provided.The pins 19 are driven into aligned holes in the inner conductors andthe supports therefor. Disposed in the slots 18 are inner conductorelements 21 and 22 formed of strips of resilient material such asPhosphor bronze. The corners of the strips are bevelled in order to makea smoother transim 2,951,925 Patented Sept. 6, 1960' 2 i tion from theround to the rectangular or strip line region and for this same reason,inner conductors 15 are of reduced diameter where they project inwardlybeyond the supports. Also they are tapered slightly beginning at a pointapproximately midway between the supports and their opposed ends. Theelements 21, 22 may be held in place in any convenient manner as by therivets' 23 shown in Fig. 2. As best shown in Fig. 1, the elements 21, 22are long enough so that they overlap one another to a slight degree, butowing to the way in which the two halves of the passageway 12 areoffset, there is no tendency for these elements to come together. Theyare, however, adapted to come in contact with the inner conductor 24 ofa standard type N female fitting disposed in one end of the passageway13, and designated generally by the numeral 25. A spacer ring 26 abutsthe inner face of the connector for purposes of electrical connection tothe actuating element of the switch 27, as will appear moreclearlyhereinafter.

More particularly, the actuating element 27 is seen to have theishape ofa portion of a hollow cylinder, that is, a sleeveor-collar witha-substantial portion thereof cut away. It is disposed in the passageway13 coaxially about the inner conductor 24 at right angles to the innerconducting elements 21 and 22. At its end remote from the connector 25,the element 27 is mounted in a bearing for rotation about its axis. Acontrolshaft 28 is rigidly'fastened to this end of the element toposition'it. At its other end, the element 27 carries a small radialflange 29. Between the flange and the spacer ring is a spring contact31, and on the opposite side of the flange bearing against the body.itself is anotherspring contact 32. In addition to providing a goodelectrical contact or ground for the preload the shaft axially.

The operation of the coaxial switch according tothe invention will bestbe understood with reference to Figs. 1 ,andi4'. In Fig. 4 the elem'ent27 is positioned by means of the shaft 28 so as to provide clearance forthe lefthand inner conducting element 21 to come in contact with theinner conductor 24. At the same time, the right-hand inner conductingelement 22 is held away from the inner conductor 24 by the actuatingelement 27 and caused to contact raised portion 33 on the switch body.This effectively grounds the inner conducting element 22 at this point.As is apparent, the actuating element also serves as an outer for theconductor 24, which effectively isolates the non-selected arm. Now ifthe element 27 is rotated, inner conducting element 21 is caused to moveaway from the conductor 24 as shown in Fig. 4. With further rotation,element 21 is adapted to come in contact with its associated raisedportion 33 on the body, while inner conducting element 22 is adapted tocome in contact with the conductor 24. As is likewise by now apparent,therefore, the switch condition is determined by the angular position ofelement 27.

In Fig. 5 there is shown the same interior portion of the switch as Fig.4 shows except that in Fig. 5 a modified form of actuating element 27 isemployed together with a strip-shaped inner conductor 24'. Actuatingelement 27 is seen to have a cylindrical outer surface with a portioncut away like element 27 but inside it is more nearly rectangular toaccommodate the strip-shaped inner conductor. In this way it is possibleto make use of a connector for the common arm which is very much thesame both mechanically and electrically as that provided for element 27atthis point, contacts'31, 32 also serve to the selectable arms.

described herein by way of example, but rather it should be deemed to belimited only to the scope of the appended claims.

What is claimed is: V

1. A switch for selectively interconnecting coaxial lines, said switchcomprising a conductive body provided with intersecting passageways,means to connect electrically the outer conductors ofsaid coaxial linesto said body, a first and a second resilient inner conductor disposed inspaced relation to one another in a first of said passageways, means tosupport the remote ends of said first and second inner conductors incantilever and to connect them electrically to the respective innerconductors of a first and second of said coaxial lines, a third innerconduc tor disposed in the other of said passageways substantially atright angles to said first and second inner conductors, said third innerconductor being adapted to be contacted by said first and second innerconductors, means to connect electrically said third inner conductor tothe inner conductor of a third of said coaxial lines, and a hollowactuating'element having/a cylindrical outer surface and being disposedaround said third inner conductor, said actuating element beingrotatably mounted and having a portion of its surface cut away toprovide clearance for a selected one of said firsttand second innerconductors to contact saidthird inner conductor while holding awayfromsaid third inner conductor the non-selected one of said first andsecond inner conductors.

- 2. A switch according to claim 1 wherein the portion of saidfirst'passagewa'y leading from said third inner conductor in onedirection is offset slightly with respect to the remaining portionleading from said inner condoctor in the opposite direction. a

3. A switch according to claim 1 wherein said actuatin element isadapted to divide said firstpassageway into two isolated portions, theone containing said first inner conductor, and the other containing saidsecond inner conductor.

4. A switch according to claim 3 wherein said body includes a contactorportion, and the non-selected one of said first and secondinner-conductors is urged into contact with said contactor portion bysaid actuating element.

5. A switch for selectively interconnecting coaxial lines,

said switch comprising a conductive body provided with intersectingpassageways, means to connect electrically the outer conductors of saidcoaxial lines to said body, a first and a second inner conductor formedof strips of resilient material and disposed in spaced relation to oneanother in the first of said passageways, said first of said passagewayshaving a rectangular sectional shape in the regions surrounding saidfirst and second inner conduc tors, means to support the remote ends ofsaid first and second inner conductors in cantilever and to connect themelectrically to the respective inner conductors of a first and second ofsaid coaxial lines, a third inner conductor disposed in the other ofsaid passageways substantially at right angles to said first and secondinner conductors, said third inner conductor being adapted to becontacted by said first and second inner conductors, means to connectelectrically said third inner conductor to the inner conductor of athird of said coaxial lines, and a hollow actuating elementhaving acylindrical outer surface and being disposed around said third innerconductor, said actuating element being rotatably mounted and having aportion of its surface cut away to provide clearance for a selected one.of said first and second inner conductors to contact-said third innerconductor while holding away the non-selected one of said first andsecond inner conductors.

6 A switch according to claim 5 including means to maintain electricalcontact between said actuating element and said body on both sides ofsaid first passageway.

7. A switch according to claim 5 wherein said first and second innerconductors have bevelled corners.

8. A switch according to claim 5 wherein said third inner conductor isformed of a strip of relatively rigid material and said actuatingelement has essentially plane inner surfaces related orthogonally.

References Cited in the file of this patent v UNITED STATES PATENTS2,427,940 Ayres Sept. 23, 1947 2,859,311 7 Concelman Nov. 4, 1958

